I tried several GTD applications to help me to organize what I have to do. The last one was Actiontastic and although I was very impressed to the easy way of working with it, I really had to return to Ready-Set-Do!
And the main reason was that this group of scripts warn me to do my reviews, something that I did not found in the other apps that I tried. At the time I defined on iCal there is a box that jumps on my screen and I have to process my Inbox itens. One other reason was that Ready-Set-Do! asks questions during the process, which helps me to put things in the right place.
And you have the other possibilities too: send to printer or to your PDA.

In the site, you can download a movie (which explains all the process) and a Free Trial. Browse the site to see everything that Ready-Set-Do! can do.